This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A163537 #14 Jul 03 2025 20:39:19 %S A163537 0,2,2,0,1,1,0,0,0,0,1,1,0,2,2,0,0,0,0,2,2,0,1,1,0,2,2,0,1,1,0,2,2,0, %T A163537 0,0,0,2,2,0,1,1,0,0,0,0,1,1,0,2,2,0,1,1,0,2,2,0,1,1,0,0,0,0,1,1,0,2, %U A163537 2,0,0,0,0,2,2,0,1,1,0,0,0,0,1,1,0,2,2,0,0,0,0,2,2,0,1,1,0,0,0,0,1,1 %N A163537 The relative direction (0=straight ahead, 1=turn right, 2=turn left) of the Peano curve A163336 at point n. %C A163537 a(9*n) = a(81*n) for all n. %H A163537 Antti Karttunen, <a href="/A163537/b163537.txt">Table of n, a(n) for n = 1..6561</a> %F A163537 a(n) = A163241((A163535(n+1)-A163535(n)) modulo 4). %F A163537 a(n) = A014681(A163536(n)). %o A163537 (Scheme) (define (A163537 n) (A163241 (modulo (- (A163535 (1+ n)) (A163535 n)) 4))) %Y A163537 Cf. A163535 (direction), A163536 (transposed relative). %K A163537 nonn %O A163537 1,2 %A A163537 _Antti Karttunen_, Aug 01 2009 %E A163537 Name corrected by _Kevin Ryde_, Aug 29 2020